Query: Add pre_get_lastpostdate filter to short-circuit get_lastpostdate()

src/wp-includes/post.php

@@ -7998,6 +7998,24 @@ function get_posts_by_author_sql( $post_type, $full = true, $post_author = null,
  * @return string The date of the last post, or false on failure.
  */
 function get_lastpostdate( $timezone = 'server', $post_type = 'any' ) {
+	/**
+	 * Pre-filter the return value of get_lastpostdate() before the query is run.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param string|false $lastpostdate The most recent time that a post was published,
+	 *                                   in 'Y-m-d H:i:s' format, or false. Returning anything
+	 *                                   other than false will short-circuit the function.
+	 * @param string       $timezone     Location to use for getting the post published date.
+	 *                                   See get_lastpostdate() for accepted `$timezone` values.
+	 * @param string       $post_type    The post type to check.
+	 */
+	$lastpostdate = apply_filters( 'pre_get_lastpostdate', false, $timezone, $post_type );
+
+	if ( false !== $lastpostdate ) {
+		return $lastpostdate;
+	}
+
 	$lastpostdate = _get_last_post_time( $timezone, 'date', $post_type );
 
 	/**

tests/phpunit/tests/post/getLastPostDate.php

@@ -61,4 +61,51 @@ public function test_get_lastpostdate() {
 		$this->assertSame( $post_post_date_last, get_lastpostdate( 'blog', 'post' ) );
 		$this->assertSame( $book_post_date_last, get_lastpostdate( 'blog', 'book' ) );
 	}
+
+	/**
+	 * @ticket 63614
+	 */
+	public function test_pre_get_lastpostdate_filter_short_circuits_query() {
+		global $wpdb;
+
+		self::factory()->post->create(
+			array(
+				'post_date' => '2020-02-28 16:09:28',
+			)
+		);
+
+		$filter = new MockAction();
+		add_filter( 'pre_get_lastpostdate', array( $filter, 'filter' ), 10, 3 );
+		add_filter(
+			'pre_get_lastpostdate',
+			static function () {
+				return '2001-01-01 00:00:00';
+			}
+		);
+
+		$num_queries = $wpdb->num_queries;
+		$result      = get_lastpostdate( 'blog', 'post' );
+
+		$this->assertSame( '2001-01-01 00:00:00', $result, 'The filtered value should be returned.' );
+		$this->assertSame( $num_queries, $wpdb->num_queries, 'No database queries should be run.' );
+		$this->assertSame( 1, $filter->get_call_count(), 'The filter should be called once.' );
+		$this->assertSame( array( false, 'blog', 'post' ), $filter->get_args()[0], 'The filter should receive the default value, timezone, and post type.' );
+	}
+
+	/**
+	 * @ticket 63614
+	 */
+	public function test_pre_get_lastpostdate_filter_returning_false_does_not_short_circuit() {
+		$post_date = '2020-02-28 16:09:28';
+
+		self::factory()->post->create(
+			array(
+				'post_date' => $post_date,
+			)
+		);
+
+		add_filter( 'pre_get_lastpostdate', '__return_false' );
+
+		$this->assertSame( $post_date, get_lastpostdate( 'blog', 'post' ) );
+	}
 }